The introduction of electric flight controls and the greater level of automation of modern transport airplanes have made it possible to significantly improve their safety. This technological leap has allowed the formulation of more secure piloting laws—in particular implemented by the automatic pilot—which participate actively in the protection of airplanes, in particular during abnormal situations, faults with the flight systems, dangerous environmental conditions, etc.
However, the use of numerous piloting laws has increased the dependency of flight systems on the measurements of the parameters of the state of an airplane. In particular, certain flight parameters now turn out to be indispensable for ensuring the flight of an airplane, so that it becomes necessary to have reliable values of these parameters. The indispensable parameters include, in particular, the anemometric and inertial parameters, their processing being performed by the ADIRS system (the acronym standing for “Air Data and Inertial Reference System”) which delivers information pertaining to the speed, the altitude and the inertial data (in particular the trim) of the airplane.